Dimmit County, Texas Natural Disaster Risk
FEMA National Risk Index assessment · TX
Very LowComposite Risk Score
National percentile: 36th
Dimmit County faces very low composite natural disaster risk (NRI Risk Index score 35.9, 36th national percentile), driven primarily by heat wave and drought exposure. Expected annual loss across all 18 hazard types is $6M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Dimmit County at very low composite risk, with a National Risk Index score of 35.9 out of 100 — placing it in the 36th national percentile and among the lowest-risk counties in the country. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at Medium risk — $3M in expected annual loss and about 7.05 events per year; drought (extended dry periods that stress water supplies and agriculture) at Medium risk — $537K in expected annual loss and about 105.87 events per year; and hurricane (tropical cyclones bringing extreme wind, rain, and storm surge) at Low risk — $137K in expected annual loss and about 0.04 events per year. Across all hazards, FEMA estimates $6M in expected annual loss for a population of 9K.
Beyond physical exposure, Dimmit County has a very high social vulnerability rating (how susceptible the population is to harm) and a very low community resilience rating (its capacity to prepare for and recover from disasters). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
History supports the rating: Dimmit County has received 17 federal disaster declarations since 1984, including 4 for hurricane events and 3 for fire events. The most recent was Severe Winter Storms (severe ice storm), declared in February 2021.
Among 254 Texas counties, Dimmit County ranks #156 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Heat Wave | Medium | 7.05 / yr | $3M |
| Drought | Medium | 105.87 / yr | $537K |
| Hurricane | Low | 0.04 / yr | $137K |
| Wildfire | Very Low | 0.00 / yr | $34K |
| Cold Wave | Low | 0.37 / yr | $551K |
| Lightning | Low | 34.94 / yr | $87K |
| Tornado | Low | 0.10 / yr | $250K |
| Ice Storm | Very Low | 0.06 / yr | $14K |
| Hail | Very Low | 0.79 / yr | $46K |
| Riverine Flood | Very Low | 1.71 / yr | $1M |
| Winter Weather | Very Low | 1.05 / yr | $6K |
| Earthquake | Very Low | 0.00 / yr | $5K |
| Strong Wind | Very Low | 0.24 / yr | $24K |
| Landslide | Very Low | 0.11 / yr | $5 |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Dimmit County has received 17 federal disaster declarations since 1984, most recently Severe Winter Storms in February 2021. Most frequent causes: Hurricane (4), Fire (3), Severe Ice Storm (2).
| Declared | Type | Disaster |
|---|---|---|
| February 2021 | Severe Ice Storm | Severe Winter Storms |
| February 2021 | Severe Ice Storm | Severe Winter Storm |
| July 2020 | Hurricane | Hurricane Hanna |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| February 2019 | Flood | Severe Storms and Flooding |
| March 2008 | Fire | 322 Fire |
| March 2008 | Fire | Wildfires |
| January 2006 | Fire | Extreme Wildfire Threat |
| September 2005 | Hurricane | Hurricane Rita |
Showing the 10 most recent of 17 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Dimmit County?
Dimmit County has a composite FEMA National Risk Index score of 35.9 out of 100, placing it in the Very Low category and the 36th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Dimmit County?
The three highest-rated hazards are Heat Wave (Medium, $3M EAL), Drought (Medium, $537K EAL), Hurricane (Low, $137K EAL). These account for most of the county's expected annual losses.
How does Dimmit County compare to other Texas counties?
Dimmit County ranks #156 of 254 Texas counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Dimmit County had?
FEMA records 17 federal disaster declarations for Dimmit County since 1984, most often 4 for hurricane events and 3 for fire events. The most recent was Severe Winter Storms, declared in February 2021.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Dimmit County's $6M EAL is a statistical average, not a guarantee for any specific year or address.